Method for loading a green tyre for bicycle in a vulcanisation mould and apparatus for moulding and vulcanising

ABSTRACT

A green tyre ( 2 ) for bicycles is built, comprising at least one carcass ply ( 4 ) having axially opposite end flaps ( 4   a ) engaged with respective bead cores ( 5 ) and a tread band ( 6 ) applied in a radially outer position around said at least one carcass ply ( 4 ). The built tyre ( 2 ) removed from the building drum, is profiled so as to translate the tread band ( 6 ) in a radially outer direction with respect to the bead cores ( 5 ), so as to impart a cross-sectional convex profile to the tyre ( 2 ) in a radially outer direction. The profiled tire is engaged by means of a transfer member ( 31 ) comprising a gripping device ( 30 ) which holds it hanging and loads it into a vulcanisation mould ( 101 ) by axially positioning an axial centreline plane (M) of the green tyre at an axial reference ( 51 ) arranged at a predetermined height along a reference axis (K) of a central body ( 103 ) of the vulcanisation mould ( 101 ).

This application is a national phase entry application under 35 U.S.C. §371 based on International Application No. PCT/IB2017/057482, filed Nov.29, 2017, which claims the priority of Italian Patent Application No.102016000131421, filed Dec. 28, 2016; the content of each applicationexpressly incorporated herein by reference.

The present invention relates to a method for loading a green tyre forbicycle in a vulcanisation mould and an apparatus for moulding andvulcanising said green tyre for bicycle.

The building of a tyre for bicycles usually provides that one or morecarcass plies are applied according to a cylindrical configurationaround an outer surface of a building drum. Each bead core of a pair ofbead cores is fitted or applied around one of the axially opposite endflaps of the carcass ply. The end flaps are then turned up around therespective bead cores. A tread band is then applied around the carcassply lying against the building drum, in an axially centred position withrespect to the bead cores.

The mutual axial distance between the bead cores remains unchangedduring the entire building process, including the application of thetread band. This process aspect represents a unique feature thatdistinguishes bicycle tyres from tyres for motor vehicles. For thelatter, in fact, a mutual approach step of the bead cores is normallyprovided to shape the carcass structure according to a toroidalconfiguration in the coupling step with the belt structure.

Once the building has been completed, the built green tyre for bicycleis removed from the drum to be transferred in a mould or a vulcanisationpress, where the tyre itself is subjected to a moulding andvulcanisation treatment aimed at determining the structuralstabilisation thereof via cross-linking of the elastomeric materialpresent therein, as well as optionally imprinting a desired treadpattern on the tread band.

The term “elastomeric material” is used to designate a compositioncomprising at least one elastomeric polymer and at least onereinforcement filler. Preferably, such a composition further comprisesadditives such as cross-linking agents and/or plasticisers. Due to thepresence of the cross-linking agents, such a material can becross-linked by heating so as to form the final manufactured article.

The terms “radial” and “axial” and the expressions “radiallyinner/outer” and “axially inner/outer” are used with reference to theradial direction of the tyre (i.e. to a direction perpendicular to theaxis of rotation of the tyre) and to the axial direction of the tyre(i.e. to a direction parallel to the axis of rotation of the tyre). Theterms “circumferential” and “circumferentially” are instead used withreference to the annular development of the tyre. A radial plane of thetyre contains the axis of rotation thereof.

The expressions “low”, “below”, “lower” or “inferiorly”, and “high”,“above”, “upper” or “superiorly” are used to designate a relativeposition of an element with respect to another and/or of an element withrespect to the ground.

“Geometric axis of rotation” of a green tyre means the axiscorresponding to the axis of rotation of the vulcanised tyre whenmounted in operating conditions on a respective mounting rim.

The term “axial centreline plane” of the moulded and vulcanised or greentyre is used to designate a plane perpendicular to the geometric axis ofrotation and equidistant from the axially outer portions of the tyreitself.

The term “gripping axis” of a gripping device is used to designate areference axis around which a gripping sector is arranged, comprising atleast one gripping area, activated on the green tyre.

The term “tyre width” is used to designate the maximum axial dimensionof the moulded and vulcanised tyre.

There essentially are at least two types of vulcanisation press forbicycle tyres, with single location and multiple location, respectively.

Single-location presses are provided with a single vulcanisation mould,normally made of two half-parts, housing a radially expandablevulcanisation bladder, fixed around a central support.

The green tyre coming from the building line is picked up by an operatorto be fitted around the vulcanisation bladder. The half-parts of themould are closed and the bladder, previously mounted inside thevulcaniser, is inflated with pressurised steam or compressed air, ornitrogen or a mixture of the previous fluids, so as to press the tyreagainst the inner walls the mould and cause the vulcanisation thereof byheat. At the end of the vulcanisation, the mould half-parts are movedaway from each other and the operator picks up the vulcanised tyre toreplace it with a new green tyre to be vulcanised. This machineconfiguration, where each mould has a relative bladder previouslymounted on the vulcaniser, can generally have up to two, three mouldsstacked on top of each other.

There are also multiple-location vulcanisation presses, includingmultiple vulcanisation moulds stacked vertically on top of each other,generally up to a maximum of 7 moulds where, however, the bladder is notfixed on the vulcaniser. The use of multiple-location presses withoutfixed bladder or so-called central mechanism requires that an operatorprovides to introduce an expandable tubular chamber within each greentyre built to be treated. The operator then introduces each tyre coupledto the respective vulcanisation chamber between the half-parts of eachvulcanisation mould, making sure that each chamber is connected to asteam feeding conduit, or compressed air, or nitrogen or a mixture ofthe previous fluids, by means of valve members provided for thispurpose. At the end of the vulcanisation, the half-parts of each mouldare moved away from each other and the operator picks up the vulcanisedtyre to replace it with a new green tyre to be vulcanised and remove thevulcanisation chamber from each vulcanised tyre.

There are multiple-location presses in which the opening and closingcycles of the moulds and of vulcanisation are carried out simultaneouslyon all tyres loaded into the press. In other cases, a sequential openingof the moulds is carried out so as to perform the vulcanisation of thesingle tyres with interspersed times according to an on-going process.

The Applicant has noted that bicycle tyres, especially when green, areoften without a structural consistency sufficient to allow the properhandling thereof by means of mechanical devices.

This is because bicycle tyres are often provided with bead cores innon-metallic material, for example in composite material based onnatural or synthetic fibres (carbon, aramid, etc.) to allow the finishedtyre to be folding. Moreover, as stated above, bicycle tyres are oftendevoid of reinforcement belting layers interposed between the carcassply or plies and the tread band.

In particular, the Applicant has noted that once removed from thebuilding drum, a green bicycle tyre tends to deform under the effect ofinternal stresses and of its own weight, and this is done randomly anduncontrollably in circumferential direction, where the circular shape islost due to the low resistance of the bead cores, and/or in the axialdevelopment direction due to the shrinkage of the materials or theweight of the components thereof.

For these reasons, bicycle tyres are often produced using mostly manualprocesses.

The Applicant has also perceived that, in order to facilitate mechanisedhandling, it should be ensured that the green tyre can be picked upsafely and reliably and repositioned with suitable accuracy for thepurposes of subsequent processing as moulding and vulcanisation.

The Applicant therefore deems it desirable to find a solution so thatgreen tyres for bicycle can be handled by mechanised handling,maintaining a predetermined precise positioning, despite their tendencyto take a substantially random deformed development.

The Applicant has finally found that it is possible to obtain a correctand precise loading of the green tyre into the vulcanisation mouldholding said green tyre in position prior to the placement in the mould,with respect to a predetermined axial position relative to a centralbody of the vulcanisation mould, the retention in such a position on thecentral body being due to a thrust action exerted from the interioroutwards by the central body itself.

More precisely, according to a first aspect thereof, the inventionrelates to a method for loading a green tyre for bicycle in avulcanisation mould.

Preferably, it is provided to pick said green tyre keeping it hanging bymeans of a gripping device defining a gripping axis.

Preferably, it is provided to handle said gripping device which holdssaid green tyre up to aligning a geometric axis of rotation of the greentyre with a reference axis of a central body of said vulcanisationmould.

Preferably, it is provided to arrange said green tyre in a radiallyouter position with respect to said central body of the vulcanisationmould.

Preferably, it is provided to axially position said green tyre withrespect to the central body so that an axial centreline plane of thegreen tyre is arranged at an axial reference arranged at a predeterminedheight along said reference axis of the central body.

Preferably, it is provided to exert a thrust action by means of saidcentral body directed radially outwards on a radially inner surface ofthe green tyre.

Preferably, it is provided to keep said green tyre in position on thecentral body by means of said thrust action.

Preferably, it is provided to disengage said gripping device from thegreen tyre for releasing said green tyre on the central body with saidaxial centreline plane centred and positioned in an axial positioncorresponding to said predetermined height.

More precisely, according to a second aspect thereof, the inventionrelates to an apparatus for moulding and vulcanising a green tyre forbicycle.

Preferably, a gripping device is provided, defining a gripping sectordistributed around a gripping axis. Preferably, said gripping sectorcomprises at least one gripping area that can be activated on the greentyre to keep said green tyre hanging.

Preferably, at least one vulcanisation mould is provided, comprising acentral body defining a reference axis.

Preferably, the central body is configured for exerting a thrust actiondirected radially towards the exterior on a radially inner surface ofthe green tyre so as to keep said green tyre in position on the centralbody by means of said thrust action.

Preferably, a transfer member is provided comprising said grippingdevice.

Preferably, said transfer member is configured for handling saidgripping device towards said vulcanisation mould.

Preferably, a centring group is provided, configured for centring saidgreen tyre held by the gripping device with said central body byaligning said geometric axis of rotation of the green tyre with saidreference axis of the central body.

Preferably, said transfer member and said central body are configuredfor arranging said green tyre held by the gripping device in a radiallyouter position with respect to said central body.

Preferably, said transfer member and said central body are configuredfor axially positioning with respect to the central body said green tyreheld by the gripping device so that an axial centreline plane of thegreen tyre is arranged at a predetermined height along said referenceaxis of the central body.

The Applicant believes that holding in position the green tyre withrespect to a predetermined axial position relative to a central body ofthe vulcanisation mould allows a correct and precise loading of thegreen tyre in the vulcanisation mould itself. In particular, by keepingthe tyre in such a position on the central body as a result of thethrust action exerted from the interior outwards by the central bodyitself, it is possible to accurately engage the tyre itself, overcomingthe problems related to the spring back effect of the materials.

The present invention, in at least one of the above aspects thereof, canexhibit at least one of the following preferred features.

Preferably, it is provided to detect the axial position of the axialcentreline plane of the green tyre with respect to the gripping device.

Preferably, picking said green tyre by means of said gripping devicecomprises positioning said axial centreline plane of the green tyre in apredetermined axial position with respect to the gripping device.

The Applicant believes that knowing the axial position of the axialcentreline plane with respect to the gripping device, detecting it afterpicking the tyre or by accurately positioning the tyre during thegripping allows the accurate positioning in the vulcanisation mould.

Preferably, picking said green tyre comprises activating at least onegripping area of a gripping sector of the gripping device against aradially outer surface of the green tyre so as to retain said green tyrefrom the exterior.

The Applicant believes that retaining the tyre from the exterior to loadit into the vulcanisation mould prevents the problems associated withthe tendency of the green tyre to take a substantially random deformeddevelopment and allows an automatic and precise loading, preventinginterference with the vulcanisation mould.

Preferably, said gripping sector comprises a plurality of said grippingareas distributed discretely around said gripping axis.

The Applicant believes that the use of a plurality of gripping areasdiscretely distributed around the gripping axis allows a uniform grip ofthe green tyre.

Preferably, each gripping area is defined by a substantially circulararea.

Preferably, the gripping areas are circumferentially distributed aroundthe gripping axis along a same circumference.

Preferably, said gripping sector comprises a single gripping areadistributed continuously around said gripping axis.

The Applicant believes that the use of a single gripping area allows ahigh precision in the relative positioning without introducing excessivestructural and/or operating complications.

Preferably, activating said gripping area against the radially outersurface of the green tyre comprises arranging said gripping area incontact with said radially outer surface of the green tyre.

Preferably, said gripping area is activated against the radially outersurface of the green tyre exerting an attraction action acting on theradially outer surface of the green tyre moving away from the geometricaxis of rotation.

Preferably, said attraction action is exerted by means of a pneumaticsuction action adapted to generate a predetermined degree of vacuumbetween the radially outer surface of the green tyre and said at leastone gripping area.

Preferably, the pneumatic suction action is activated when the radiallyouter surface and said at least one gripping area are in mutual contact.

Preferably, prior to handling said gripping device, it is provided toverify the attainment of a predetermined degree of vacuum between theradially outer surface of the green tyre and said at least one grippingarea, said predetermined degree of vacuum being indicative of the actualgripping of the green tyre.

Preferably, disengaging said gripping device from the green tyrecomprises deactivating said at least one gripping area releasing saidradially outer surface.

Preferably, said gripping device comprises a plurality of grippingelements distributed around the gripping axis, each gripping element ofsaid plurality of gripping elements defining a gripping area.

Preferably, disengaging said gripping device from the green tyrecomprises deactivating said pneumatic suction action releasing saidradially outer surface.

Preferably, it is provided to exert, by means of a profiling unit, athrust action directed radially outwards on a radially inner surface ofthe green tyre for expanding said green tyre from the interior up toreaching an expanded configuration before picking said green tyre.

Preferably, picking said green tyre comprises activating at least onegripping area of a gripping sector of the gripping device against aradially outer surface of the green tyre in the expanded configurationso as to retain said green tyre from the exterior and keep it in theexpanded configuration.

Preferably, it is provided to cancel said thrust action exerted by saidprofiling unit before handling said gripping device towards saidvulcanisation mould.

Preferably, said gripping sector is arranged circumferentially aroundsaid gripping axis and defines an annular gripping portion.

Preferably, it is provided to select an annular gripping band of thegreen tyre arranged around the geometric axis of rotation at apredetermined height along the geometric axis of rotation itself.

Preferably, it is provided to activate said at least one gripping areaof the annular gripping portion against the radially outer surface ofthe annular gripping band.

Preferably, it is provided to carry out a relative axial translationmovement between said annular gripping portion and said annular grippingband to arrange them at the same height along the geometric axis ofrotation of the green tyre.

Preferably, activating said gripping area against the radially outersurface of the green tyre comprises arranging said annular grippingportion in contact with said annular gripping band.

Preferably, during the handling of the gripping device, the green tyreis retained by the gripping device hanging only at the annular grippingband.

Preferably, during the handling of the gripping device, said grippingdevice holds the green tyre from the outside and keeps said annulargripping band in the expanded configuration.

Preferably, said axial centreline plane symmetrically divides saidannular gripping band with respect thereto.

Preferably, said axial centreline plane symmetrically divides a treadband of the green tyre with respect thereto.

Preferably, said axial centreline plane and the respective height alongsaid reference axis of the central body are selected as a function ofthe tyre width.

Preferably, axially positioning said green tyre with respect to thecentral body comprises carrying out a relative axial translationmovement between said gripping device and said central body so as toarrange said axial centreline plane at the predetermined height alongsaid reference axis of the central body.

Preferably, axially positioning said green tyre with respect to thecentral body comprises moving said central body between a vulcanisationposition, in which said central body is arranged within thevulcanisation mould and a gripping position, in which said central bodyis arranged outside the vulcanisation mould and positioned radiallyinside the green tyre.

Preferably, said vulcanisation position is arranged at a smaller heightthan said gripping position.

Preferably, said central body exerts said thrust action on the radiallyinner surface of the green tyre when said central body reaches saidgripping position and said axial centreline plane is arranged at thepredetermined height.

Preferably, said gripping device is disengaged from the green tyre andsaid green tyre is kept in position hanging on the central body arrangedin gripping position, retained from the interior by means of said thrustaction exerted by said central body.

Preferably, the green tyre is retained from the interior only by meansof said thrust action exerted by said central body without bottomsupport.

Preferably, said central body is moved from the vulcanisation positionto the gripping position in which said central body exerts said thrustaction on the radially inner surface of the green tyre and, whilekeeping said green tyre in position on the central body by means of saidthrust action, the central body is moved from the gripping position tothe vulcanisation position for vulcanising said green tyre.

Preferably, exerting said thrust action by means of said central bodycomprises radially expanding at least one portion of the central body upto touching a radially inner surface of the green tyre.

Preferably, said portion is an expandable vulcanisation chamber.

Preferably, the axial reference is arranged at an axial centreline planeof the expandable vulcanisation chamber.

Preferably, said green tyre is maintained with said geometric axis ofrotation arranged transversely with respect to a horizontal geometricplane. Even more preferably, said green tyre is maintained with saidgeometric axis of rotation arranged vertically.

Preferably, said green tyre is picked by said gripping device with saidgripping axis and said geometric axis of rotation arranged transverselywith respect to a horizontal geometric plane. Even more preferably, saidgreen tyre is picked by said gripping device with said gripping axis andsaid geometric axis of rotation arranged vertically.

Preferably, said gripping device is handled with said gripping axisarranged transversely with respect to a horizontal geometric plane. Evenmore preferably, said gripping device is handled with said gripping axisarranged vertically.

Preferably, said green tyre is arranged and positioned with respect tothe central body arranged with said reference axis arranged transverselywith respect to a horizontal geometric plane. Even more preferably, saidgreen tyre is arranged and positioned with respect to the central bodyarranged with said reference axis arranged vertically.

Preferably, said gripping device is configured for retaining said greentyre at a radially outer surface against which said at least onegripping area is activated.

Preferably, said gripping device comprises a plurality of grippingelements distributed around said gripping axis, each gripping element ofsaid plurality of gripping elements defining a gripping area.

Preferably, the gripping elements are radially movable with respect tothe gripping axis of the gripping device between a rest configuration,in which they are radially away from the gripping axis in order todisengage said gripping device from the green tyre and a workingconfiguration, in which they are radially approached to the grippingaxis for picking said green tyre.

Preferably, said gripping elements are circumferentially distributed sothat said gripping areas define an annular gripping portion.

Preferably, said gripping elements are configured for exerting apneumatic suction action adapted to generate a predetermined degree ofvacuum between the radially outer surface of the green tyre and thegripping areas.

Preferably, each gripping element comprises a suction or spongyinterface adapted to come into contact with the radially outer surfaceof the green tyre, said interface being connected to a suction device.

Preferably, a detection device is provided for detecting the degree ofvacuum applied by the gripping elements between the radially outersurface of the green tyre and said gripping area.

Preferably, the detection device is configured for generating adetection signal indicative of the detected degree of vacuum.

Preferably, a control unit is provided, programmed for receiving saiddetection signal and comparing it with a threshold value indicative ofthe actual grip of the green tyre.

Preferably, said control unit is programmed for activating said transfermember if said comparison confirms the actual gripping of the greentyre.

Preferably, said centring group comprises a first centring portionassociated with the gripping device and a second centring portionassociated with the central body, said first and second centringportions defining a shape coupling configured for aligning saidgeometric axis of rotation of the green tyre held by the gripping deviceand said gripping axis with said reference axis of the central body.

Preferably, said gripping device comprises a frame which supports saidgripping sector, said frame being movable along the gripping axis withrespect to the first centring portion.

Preferably, at least one elastic element is interposed between the frameand the first centring portion. Even more preferably, the elasticelement is configured and arranged so as to oppose the approach betweenthe frame and the first centring portion and allow the elastic return toa predetermined relative position of the frame and of the first centringportion.

Preferably, said gripping device is configured for picking said greentyre from a profiling unit configured for receiving a green tyre forbicycle, profiling it according to a circular extension around thegeometric axis of rotation of the green tyre and according to a convexcross-sectional profile in a radially outer direction, and arrange itwith said geometric axis of rotation in a predefined position withrespect to the profiling unit itself.

Preferably, said profiling unit is configured for receiving said greentyre for bicycle with said geometric axis of rotation arrangedtransversely with respect to a horizontal geometric plane. Even morepreferably, said profiling unit is configured for receiving said greentyre for bicycle with said geometric axis of rotation arrangedvertically.

Preferably, said profiling unit is configured for exerting a thrustaction directed radially outwards on a radially inner surface of thegreen tyre for expanding said green tyre from the interior up toreaching an expanded configuration.

Preferably, said profiling unit comprises a centring mandrel having acentral geometric axis and a radially expandable profiling memberextending circumferentially around said central geometric axis.

Preferably, said profiling member comprises an expandable membrane fixedaround an outer circumferential surface of the centring mandrel.

Preferably, said profiling member comprises a plurality of sectorsradially movable with respect to said central geometric axis.

Preferably, said central geometric axis is arranged transversely withrespect to a horizontal geometric plane. Even more preferably, saidcentral geometric axis is arranged vertically.

Preferably, said gripping device is configured for retaining said greentyre hanging with said geometric axis of rotation and said gripping axisarranged transversely with respect to a horizontal geometric plane.

Even more preferably, said gripping device is configured for retainingsaid green tyre hanging with said geometric axis of rotation and saidgripping axis arranged vertically.

Preferably, said gripping device and said central body are movableaccording to a relative axial translation movement for arranging theaxial centreline plane at the predetermined height along said referenceaxis of the central body.

Preferably, said central body is movable between a vulcanisationposition, in which said central body is arranged within thevulcanisation mould and a gripping position, in which the central bodyis arranged outside the vulcanisation mould and positioned radiallyinside the green tyre.

Preferably, said central body comprises at least one portion configuredfor expanding up to touching a radially inner surface of the green tyre.

Preferably, said apparatus is configured for maintaining said geometricaxis of rotation of the green tyre arranged transversely with respect toa horizontal geometric plane.

Even more preferably, said apparatus is configured for maintaining saidgeometric axis of rotation of the green tyre arranged vertically.

Preferably, said annular gripping portion is defined by a plurality ofgripping areas circumferentially distributed around the gripping axisalong a same gripping circumference.

Preferably, the annular gripping portion is brought to a radially outerposition with respect to the annular gripping band and with saidgripping circumference aligned with an axial centreline plane of thegreen tyre.

Further features and advantages will become more apparent from thedetailed description of a preferred but non-exclusive embodiment of amethod for loading a green tyre for bicycle in a vulcanisation mould andan apparatus for moulding and vulcanising said green tyre for bicycleaccording to the present invention. Such a description is givenhereinafter with reference to the accompanying drawings, provided onlyfor illustrative and, therefore, non-limiting purposes, in which:

FIGS. 1 to 4 schematically show cross-sectional views of some operatingsteps designed to build a green tyre for bicycle;

FIG. 5 shows a perspective bottom view of a profiling unit and agripping device forming part of an apparatus for moulding andvulcanising a green tyre for bicycle according to the invention;

FIG. 6 schematically shows a top perspective view of the profiling unitin FIG. 5;

FIG. 7 schematically shows a cross-sectional view of the profiling unitwith a green tyre fitted around a profiling member in contractedcondition;

FIG. 8 schematically shows a cross-sectional view of the profiling unitin FIG. 7 during a profiling operation of the green tyre;

FIG. 9 shows a detail in FIG. 7 during the introduction of the grippingdevice of the green tyre;

FIG. 10 shows the detail in FIG. 8 during the engagement of the greentyre with the gripping device;

FIG. 11 shows the green tyre engaged with the gripping device andremoved from the profiling unit;

FIG. 12 schematically shows a transverse section view of a finished tyrefor bicycle;

FIG. 13 schematically shows a top perspective view of the grippingdevice holding a green tyre;

FIG. 14 schematically shows a side view of the gripping device in FIG.13;

FIG. 15 schematically shows a cross-sectional view of the grippingdevice in FIG. 13;

FIGS. 16-18 schematically show the apparatus for moulding andvulcanising a green tyre for bicycle according to the present invention.

An apparatus for moulding and vulcanising a green tyre for bicycleaccording to the present invention is globally designated with referencenumeral 1 (FIGS. 16-18).

The present invention is designed for processing tyres 2 for bicycle, ofthe type schematically exemplified in FIG. 12, for example for use onroad, track, mountain bikes, e-bikes, etc.

A radially inner surface 2 a, substantially facing towards a geometricaxis of rotation “X” of tyre 2, and a radially outer surface 2 bsubstantially facing away from the geometric axis of rotation “X”, canbe identified in tyre 2.

Tyre 1 for bicycle has a carcass structure 3 comprising at least onecarcass ply 4 having mutually parallel cords embedded in an elastomericmatrix.

Axially opposite end flaps 4 a of the carcass ply or plies 4 are engagedto respective bead cores 5, that is, annular anchoring structuresintegrated in the regions usually identified by the name of “beads” atwhich the mechanical engagement between tyre 2 in use conditions and arespective mounting rim takes place.

A tread band 6, made of elastomeric material, is applied in a radiallyouter position with respect to the carcass structure 3.

Preferably, at least two layers of cords having a cross pattern,respectively, can be identified in the carcass structure 3. The cordsbelonging to each layer have an inclined development according to apredetermined angle, approximately between about 35° and about 65° withrespect to a circumferential development direction of tyre 2. Forexample, the presence of two carcass plies 4 may be provided, radiallysuperimposed on top of each other, each with the respective cordsextending along an inclined direction with respect to thecircumferential development of tyre 2 and according to an inclinedorientation with respect to the cords belonging to the other carcass ply4.

Alternatively, as shown in FIG. 12, a single carcass ply 4 may beprovided, the end flaps 4 a whereof, turned up around bead cores 5,extend at least up to an axial centreline plane “M” of tyre 2, so as todefine each a further radially outer layer of cords having crossedorientation with respect to the cords present in the radially innerlayer.

Unlike the tyres typically designed to be used on motor vehicles, tyre 2for bicycle is generally devoid of a belt structure, that is, ofreinforcement belt layers radially interposed between the carcassstructure 3 and the tread band 6. In tyres for motor vehicles, thesebelt layers contribute to increasing the structural strength of tyre 2and to stabilising the geometry thereof, especially in the crown region,i.e. in the radially outer regions closer to the tread band 6.

In tyre 2 for bicycle, however, at least one circumferential protectivelayer 7 may be provided, interposed between the tread band 6 and thecarcass structure 3. Where present, said at least one circumferentialprotective layer 7, the task whereof is essentially to protect tyre 2from puncture, may have a textile structure or be made in the form ofcontinuous layered tape of synthetic material, and preferably has athickness not larger than about 0.5 mm, preferably not smaller thanabout 0.2 mm.

Unlike a real belt structure, the circumferential protective layer orlayers optionally present in tyre 2 for bicycle do not significantlyinfluence the structural strength, geometric stability and/or dynamicbehaviour of tyre 2 itself.

Preferably, on the radially outer surface 2 b of tyre 2 for bicycle,portions of carcass ply 4 directly exposed towards the externalenvironment can be identified between the axially outer edges of thetread band 6 and the bead cores 5. Tyre 2 for bicycle is in facttypically not provided with sidewalls, i.e. layers of elastomericmaterial applied laterally outside the carcass structure 3, eachextending between one of the beads and the respective axially outer edgeof the tread band.

In tyre 2 for bicycle, thickness “S” of the bead core 5 corresponds to ahalf of the difference between an outer circumferential diameter “De”and the seating diameter “Dc” of bead core 5 itself.

As schematised in FIGS. 1 to 4, the building of tyre 2 for bicycle infact provides that, using suitable application devices (not shown)forming part of a building unit, the carcass ply or plies 4 aredeposited according to a cylindrical configuration, such as by wrappingaround an outer surface of a building drum 9.

By means of bead core application devices (not shown), a pair of beadcores 5, for example made of composite material based on natural orsynthetic fibres and/or more seldom, metallic material, is applied at afixed mutual axial distance “D”, each around one of the axially oppositeend flaps 4 a of the carcass ply 4.

In particular, in the example shown, it is provided that each bead core5, previously made in the form of finished component, is first fittedaround the carcass ply or plies 4 in an axial position corresponding toa circumferential recess 10 formed on the building drum 9 A slightradial expansion of the building drum 9, for example by lever mechanismsforming part of said bead core application devices, causes theapplication of the bead cores 5 against the carcass ply or plies 4, eachat the respective circumferential recess 10.

Alternatively, the bead core application devices may be configured tomake each bead core 5 directly on the building drum 9, wrapping one ormore continuous cords around the carcass ply or plies 4 according to aplurality of coils axially juxtaposed and/or radially superimposed oneach other.

Turning up devices (not shown) operating at the building drum 9 thenturn up the end flaps 4 a of the carcass plies 4 around the respectivebead cores 5. During the turning up, the end flaps 4 a may be at leastpartially superimposed on each other and optionally joined in mutualdirect contact.

Tread band application devices (not shown) aid the application of atread band 6 around the carcass ply 4, in an axially centred positionwith respect to the bead cores 5. The tread band 6 may be applied inradial superimposition with respect to the turned up end flaps 4 a. Oncethe application has been completed, the turned up end flaps 4 a maytherefore be partly arranged in an axially inner position with respectto axially opposite edges of the tread band.

On occurrence, the application of the tread band 6 may be preceded bythe application of said at least one circumferential protective layer 7.

During the application of the tread band 6, an axially central portionof said at least one carcass ply 4, extending axially through an axialcentreline plane “M” equidistant from the bead cores 5, lies against thebuilding drum 9 (FIG. 4).

The tread band 6 is preferably applied maintaining the mutual axialdistance “D” of the bead cores 5 virtually unchanged. More inparticular, the mutual axial distance “D” between the bead cores 5preferably remains unchanged during the entire building process,including the application of the tread band 6.

Once the building has been completed, the green tyre 2 is removed fromthe building drum 9 to be subjected to other process steps, for exampleto be transferred to a vulcanisation press or mould.

To this end, the building drum 9 is radially contracted so as tofacilitate the axial removal of the built tyre 2. Being devoid of beltstructure and having generally bead cores 5 made from natural orsynthetic fibres (carbon, aramid, etc.), tyre 2 for bicycle tends todeform spontaneously or very easily, for example under the effect of itsown weight, as soon as it is removed from the building drum 9. In otherwords, upon removal from the building drum 9, tyre 2 loses its shapewith circular development, taking a deformed development in a random anduncontrolled manner.

Moreover, any residual elastic tensions resulting for example from theradial expansion imposed during the application of the bead cores 5induce the carcass ply or plies 4 to resume their original diameter,especially at the axially central portion. As a result, tyre 2 initiallybuilt according to a cylindrical shape, tends to take a cross-sectionalprofile substantially convex towards a radially inner direction.

The present invention aims to allow a reliable loading of the built tyre2 for bicycle, for the transfer thereof to a vulcanisation press ormould 101.

With reference to FIGS. 5-11, reference numeral 11 indicates a profilingunit, comprising a centring mandrel 12 having a central geometric axis“Y”, preferably oriented transversely to a horizontal plane “O”, forexample according to a vertical direction, i.e. perpendicular thereto.

The centring mandrel 12 comprises a support structure 13 supporting acentral upright 14 to which a support plate 15 is fixed, preferablycircular in shape, having a peripheral edge extending concentrically onthe central geometric axis “Y”.

A coupling shank 16 tubular in shape, having a truncated-cone upper end,is preferably fixed on an upper surface of the support plate 15,concentrically to the central geometric axis “Y”.

The centring mandrel 12 is operatively coupled to a radially expandableprofiling member 17, extending circumferentially around the centralgeometric axis “Y” and preferably arranged peripherally on the uppersurface of the support plate 15.

Preferably, the profiling member 17 comprises an expandable membrane 18extending around the central geometric axis “Y”.

The expandable membrane 18 is preferably fixed around a support collar19 fixed to the support plate 15 concentrically to the central geometricaxis “Y”. The expandable membrane 18 is adapted to be inflated throughthe controlled introduction of air or other operating fluid underpressure through one or more passages formed, for example, through thesupport collar 19, to radially expand away from the central geometricaxis “Y”.

In a possible alternative embodiment not shown, the profiling member 17may optionally comprise, in addition to or in replacement of theexpandable collar 18 and the support collar 19, a plurality of sectorsradially movable with respect to said central geometric axis “Y”.

The profiling unit 11 is adapted to operatively engage the built greentyre 2, which can be fitted around the profiling member 17, for exampleby manual intervention of an operator.

The profiling unit 11 is further preferably provided with axialpositioning devices 20 of the green tyre 2 along the central geometricaxis “Y” of the centring mandrel 12.

Such axial positioning devices 20 may for example comprise acircumferential support 21 having at least one circumferentialsupporting surface 21 a concentric to the central geometric axis “Y” andprotruding in a radially outer direction with respect to said profilingmember 17, for supporting tyre 2 in supporting relation at an axiallyouter edge thereof, for example defined by one of the beads arrangedinferiorly.

The circumferential support 21 and the centring mandrel 12 are mutuallypositionable along a direction parallel to the central geometric axis“Y”, so as to facilitate the adaptation of the profiling unit 11 to theprocessing of tyres 2 having respectively different widths.

To this end, it may for example be provided that the circumferentialsupporting surface 21 a of the circumferential support 21 is defined bya plurality of elastically movable sheets peripherally borne by asupport ring 23 so as to be circumferentially distributed around thecentral geometric axis “Y”. Each sheet 22 may for example comprise anattachment portion 22 a fixed to the support ring 23 and extending awayfrom the latter parallel to the central geometric axis “Y”, and asupporting portion 22 b extending transversely from one end of theattachment portion 22 a, in a distanced position with respect to thesupport ring 23.

Preferably, the support ring 23 engages the centring mandrel 12 slidablyalong a direction parallel to the central geometric axis “Y”. To thisend, the circumferential support 21 may be provided with one or morerunners 24, for example borne by a radial structure 25 integral with thesupport ring 23. Runners 24 are operatively engaged along respectiveguide rods 26 protruding inferiorly from the support plate 15 of thecentring mandrel 12.

An interchangeable calibrated insert 27, removably engaged between theradial structure 25 and an abutment 28 inferiorly borne by the supportplate 15, stops the descent of the centring mandrel 12 at apredetermined height with respect to the circumferential support 21. Theavailability of a plurality of calibrated inserts 27 may be provided,having different dimensions and selectively usable as a function of theaxial dimension of the green tyre 2 being processed.

The presence of the correct calibrated insert 27, pre-selected as afunction of the axial dimension of the tyres being processed, makes thegreen tyre 2 fitted around the centring mandrel 12, coming into contactwith the circumferential supporting surface 21 a, arrange itself withrespect to the profiling member 17 in a predetermined axial positionalong the central geometric axis “Y”. More precisely, the green tyre 2is stopped and supported in a position such that the axial centrelineplane “M” thereof coincides with an axial centreline plane “M” of theexpandable membrane 18, or other type of profiling member 17.

Preferably, sheets 22 are spaced apart from the central geometric axis“Y” by a greater extent than a maximum radius of the profiling member 17with respect to the central geometric axis “Y” itself, at least in theradially contracted condition. It is therefore possible to preventmechanical interference between sheets 22 and the profiling member 17,during a mutual axial handling thereof.

The profiling member 17 is adapted to be activated, for example byintroducing operating fluid in the expandable membrane 18, when thegreen tyre 2, previously fitted around the profiling member 17, issupported by the circumferential supporting surface 21 a.

To this end, it may be provided that the activation control of theprofiling member 17 takes place by a control unit “C” (not shown), uponreceipt of an enabling signal emitted by sensor members 29 designed todetect the presence of tyre 2 around the profiling member 17 itself.Such sensor members 29 may for example comprise an optical detectororiented towards the profiling member 17. The optical detector isconfigured to emit a presence signal when tyre 2 is interposed betweenthe profiling member 17 and the optical detector itself.

The expandable membrane 18 or other profiling member 17 is consequentlyexpanded from a radially contracted condition (FIG. 7) to a radiallyexpanded condition (FIG. 10).

Preferably, in the contracted condition, the profiling member 17 has amaximum diameter smaller than the seating diameter “Dc”, so as to haveat least one portion distant from the radially inner surface 2 a of thebuilt tyre 2. In the expanded condition, the profiling member preferablyhas, at least in the vicinity of the axial centreline plane “M”, amaximum diameter greater than the seating diameter, so as to operateagainst the radially inner surface 2 a of tyre 2, exerting a thrustaction in a substantially radial direction from the inside towards theoutside (centrifugal) to expand the green tyre from the interior up toreaching an expanded configuration.

On the effect of such a thrust action, the green tyre 2 is thereforesubjected to a restoration of the development so as to take again acircular configuration around the geometric axis of rotation “X”. At thesame time, tyre 2 is centred with the geometric axis of rotation “X”thereof coincident with the central geometric axis “Y” of the centringmandrel 17 and of the profiling member 17.

The expansion of the expandable membrane 18, moreover, tends totranslate the tread band 6 towards a radially outer direction withrespect to the bead cores 5, so as to impart a cross-sectional convexprofile to the green tyre 2 towards a radially outer direction.

In order to facilitate the profiling of tyre 2 in the manner describedabove, the initial contact between the expandable membrane 18 and thebuilt tyre 2 preferably takes place in the vicinity of the axialcentreline plane “M” of tyre 2 itself.

Since the green tyre 2 positioned around the profiling member may have asignificantly deformed configuration, it is preferable that theprofiling of tyre 2 itself is not carried out by a single expansionaction, but by two or more expansion actions cyclically repeated andalternating with respective contraction actions. It may further beprovided that such cyclically repeated expansion actions follow oneanother respectively with progressively increasing intensity.

More in particular, a first expansion action may be carried out byimposing a relatively small expansion to the profiling member 17 withrespect to that imposed during a subsequent expansion action. In theexample shown, to this end it may be provided that the first expansionaction is carried out by feeding operating fluid in the expandablemembrane 18 at a first pressure value, suitable for determining asufficient circumferential stretching of tyre 2. In particular, the tyremay thus be stretched according to a circular configuration coaxially tothe central geometric axis “Y”. For example, the first expansion actionmay be carried out by feeding the operating fluid at a pressure ofbetween about 10 KPa and about 150 KPa, for a time indicatively ofbetween about 1 s and about 25 s. As a result of the first expansionaction, the profiling member 17 is preferably brought to a semi-expandedcondition, intermediate between the contracted condition and theexpanded condition (FIG. 8).

The operating fluid is then discharged from the expandable membrane 18to determine a first contraction, so as to obtain the detachment,preferably complete, from the inner surface of tyre 2.

Immediately after the contraction, indicatively within a time notexceeding about 30 s, operating fluid is again introduced in theexpandable membrane 18 at a higher pressure than the first value, so asto determine a second expansion action and subsequent profiling of tyre2. For example, the second expansion action may be carried out byfeeding the operating fluid at a pressure of between about 10 KPa andabout 150 KPa, for a time indicatively of between about 1 s and about 25s. As a result of the second expansion action, the profiling member 17can be brought to the expanded condition.

Since the green tyre 2 is already pre-profiled due to the firstexpansion action, the action of the expandable membrane 18 during thesecond expansion action may be more uniform, so as to facilitate theprofiling of tyre 2 without causing distortions due to localisedstresses.

On occurrence, more than two expansion action interspersed withrespective contraction actions may be provided.

In use, the profiling unit 11 allows receiving and arranging a greentyre 2 for bicycle profiled according to a circular development around ageometric axis of rotation “X” thereof and according to across-sectional convex profile in a radially outer direction. Thegeometric axis of rotation “X” is therefore arranged in a predefinedposition with respect to the profiling unit 11. Preferably, theprofiling unit 11 is configured for receiving the green tyre for bicyclewith the geometric axis of rotation “X” arranged transversely withrespect to a horizontal geometric plane “O”, even more preferablyvertically.

After or concurrently with the execution of the profiling action, thegreen tyre 2 is adapted to be engaged by a gripping device 30 borne by atransfer member 31. The transfer element 31 provides to remove the greentyre from the profiling unit 11 and is configured for handling thegripping device 30 towards at least a subsequent working station, suchas a vulcanisation press 101, while the gripping device 30 continues toretain the green tyre.

Preferably, the transfer member 31, for example comprising a roboticarm, preferably of the anthropomorphic type with at least six axes, orother handling unit, is configured to engage the green tyre 2 by thegripping device 30, while tyre 2 itself is mechanically retained so asto maintain said cross-sectional convex profile in a radially outerdirection.

The gripping device 30 defines a gripping sector 32 distributed around agripping axis “Z” and comprising at least one gripping area 33 which canbe activated on the green tyre. When the gripping device 30 retains thegreen tyre 2, the gripping axis “Z” coincides with the geometric axis ofrotation “X”, therefore, in this situation, reference will be madewithout distinction to the one or the other in the continuation of thepresent description.

According to a possible embodiment, of which the accompanying drawingsare a non-limiting example, the gripping sector 32 comprises a pluralityof gripping areas 33 distributed discretely around the gripping axis.Preferably, each gripping area 33 is defined by a substantially circulararea. Preferably, the gripping areas are circumferentially distributedaround the gripping axis “Z” along a same gripping circumference 34.

According to an alternative embodiment, the gripping sector 32 maycomprise a single gripping area distributed circumferentially around thegripping axis.

In particular, the gripping area 33 is activated against a radiallyouter surface of the green tyre 2 so as to retain it. In particular, theactivation of the gripping area 33 generates an attraction action “A”acting on the radially outer surface of the green tyre moving away fromthe geometric axis of rotation “X”. In the case of a plurality ofgripping areas 33, the activation thereof generates a plurality ofattraction actions “A” distributed around the geometric axis of rotation“X”.

Such attraction action(s) is/are exerted by means of a pneumatic suctionaction adapted to generate a predetermined degree of vacuum between theradially outer surface of the green tyre and the respective grippingarea.

Preferably, the gripping sector 32 is arranged circumferentially aroundthe gripping axis “Z” and defines an annular gripping portion. In otherwords, with reference to the embodiment shown in the accompanyingdrawings in which a plurality of gripping areas 33 is provided,distributed discretely circumferentially around the geometric axis ofrotation “X”, the gripping sector 32 corresponds to the region of thegripping device 30 intended to interact with the green tyre and formedby a sequence of gripping areas 33.

Preferably, the gripping device 30 is configured for retaining the greentyre hanging with the geometric axis of rotation “X” thereof and thegripping axis “Z” arranged transversely with respect to a horizontalgeometric plane “O”, preferably vertical. The gripping device 30preferably comprises gripping elements 35 distributed around thegripping axis “Z” and defining each a gripping area 33 of tyre 2.Preferably, the gripping elements 35 are circumferentially distributedso that the gripping areas 33 define the annular gripping portion.

An adjustment apparatus 36 is configured for arranging each grippingarea 33 in predetermined radial positions with respect to the grippingaxis “Z” and thus with respect to the geometric axis of rotation “X” ofthe green tyre. Preferably, the adjustment apparatus comprises at leastone driving actuator 37. On the action of the driving actuator 37, thegripping elements 35 and thus the gripping areas 33 are radially movablewith respect to the gripping axis “Z”, between a rest condition, inwhich they are radially spaced apart with respect to the gripping axis“Z” (FIG. 9), and a working condition in which they are radiallyapproached with respect to the gripping axis “Z” (FIGS. 10 and 11).

Preferably, the driving actuator 37 is configured for adjusting theradial position of the gripping elements 35 up to reaching a restconfiguration corresponding to a radial adjustment position arrangedwith respect to the geometric axis of rotation “X” of the green tyre atan adjustment distance larger than the radius of the radially outersurface of the green tyre to be retained.

Moreover, the driving actuator 37 is configured for adjusting the radialposition of the gripping elements 35 up to reaching a workingconfiguration corresponding to a radial gripping position arranged withrespect to the geometric axis of rotation “X” of the green tyre at agripping distance smaller than the adjustment distance.

In the case of the annular gripping portion, the driving actuator 37 isconfigured for adjusting the annular gripping portion to an adjustmentdiameter larger than the outer diameter of an annular gripping band ofthe green tyre, corresponding to the rest configuration, andsubsequently to a gripping diameter, smaller than the adjustmentdiameter, corresponding to the working configuration.

It may be provided that a single driving actuator 37 operatessimultaneously on multiple gripping elements 35, preferably all, forexample through a handling mechanism 38 configured to radially move themin a simultaneous and synchronised manner.

Each gripping element 35 may for example comprise a support 39, such asplate-shaped and extending parallel to the gripping axis “Z” and havingan upper end constrained to the handling mechanism 38 and a lower enddefining the gripping area 33.

According to a possible embodiment of which the accompanying examplesare a non-limiting example, the handling mechanism 38 comprises a camdisc 40 handled in rotation around the gripping axis “Z” by the drivingactuator 37 and a plurality of rollers 41, each associated with asupport 39. Supports 39 are radially movable along a spoke 42 of aradial element 43. An elastic return device 44 is interposed betweeneach support 39 and the radial element 43. As a result of an actuationof the driving actuator 37, the cam disc 40 rotates according to arrow“R” in FIG. 13 and causes the radial centrifugal displacement ofsupports 39 in contrast to the elastic return device 44. The rotation inthe opposite direction of the cam disc 40 allows the centripetal radialdisplacement of supports 39 by the effect of the elastic return device44.

According to a possible alternative, not shown, a plurality of actuatorsis configured for autonomously adjusting the radial position of eachgripping element 35 or groups of gripping elements.

According to a possible embodiment, the gripping elements 35 may bearranged in groups and each group is associated with a driving actuatorconfigured for adjusting the radial position thereof in a simultaneousand synchronised manner or autonomously.

Preferably, the gripping elements 35 are configured for exerting apneumatic suction action adapted to generate a predetermined degree ofvacuum between the radially outer surface 2 b of the green tyre and thegripping areas 33. Preferably, each gripping element 35 comprises asuction or spongy interface 45 adapted to come into contact with theradially outer surface of the green tyre 2. Preferably, interface 45 isconnected to a suction device by means of a suction conduit.

According to a possible embodiment, of which the accompanying drawingsare a non-limiting example, interface 45 defines a gripping area 33.

Preferably, a detection device 46 is provided for detecting the degreeof vacuum applied by the gripping elements between the radially outersurface of the green tyre 2 and the gripping areas 33 and for generatinga detection signal indicative of the vacuum degree detected. Preferably,the control unit “C” is programmed for receiving the detection signal,comparing it with a threshold value indicative of the actual gripping ofthe green tyre 2 and activating the transfer member 31 if the abovecomparison confirms the actual gripping of the green tyre.

A centring group 47 is configured for aligning the gripping axis “Z”with the geometric axis of rotation “X” of the green tyre arranged inthe profiling unit 11 and thus with the central geometric axis “Y” ofthe profiling member 17.

According to a possible embodiment, the centring unit 47 comprises afirst centring portion associated with the gripping device 30 and asecond centring portion associated with the profiling unit 11. Inparticular, the first and second centring portion define a shapecoupling configured for aligning the gripping axis “Z” with thegeometric axis of rotation “X” of the green tyre arranged in theprofiling unit 11, i.e. with the central geometric axis “Y” of theprofiling member 17.

According to the embodiment shown, the first portion associated with thegripping device 30 is implemented by a tailstock 48 tubular in shape,having an upper end of with truncated-cone shape. The second centringportion associated with the profiling unit 11 is implemented by saidcoupling shank 16.

Preferably, the gripping device 30 comprises a frame 49, for examplecomprising the radial element 43, supporting the gripping sector 32.Frame 49 is movable along the gripping axis “Z” with respect to thefirst centring portion. Preferably, at least one elastic element 50 isinterposed between 49 frame and the first centring portion. According tothe example shown, the elastic element 50 is configured and arranged soas to oppose the approach between frame 49 and the first centringportion and allow the elastic return to a predetermined relativeposition of frame 49 and of the first centring portion.

With reference to FIGS. 7-11, the profiling unit 11 arranges theprofiled green tyre as described above and provides it to the grippingdevice 30 to be loaded into the vulcanisation mould 101.

The gripping axis “Z” of the gripping device 30 not associated with agreen tyre is aligned with the geometric axis of rotation “X” of thegreen tyre arranged in the profiling unit 11 and thus with the centralgeometric axis “Y” of the centring mandrel 12. This alignment isdesigned to coaxially position the gripping device 30 around the greentyre. In particular, the transfer member 31 places the gripping device30 with the gripping elements 35 arranged in the rest configurationcoaxially above the profiling unit 11.

An axial translation, for example descent, of the gripping device 30 isthen determined along the gripping axis “Z”, to obtain the mutualengagement between the coupling shank 16 and tailstock 48 counter-shapedthereto, coaxially borne by the gripping device 30. The engagement oftailstock 48 with the coupling shank 16 defines a shape couplingconfigured to determine a precise alignment of the gripping device 30with the gripping axis “Z” thereof coaxially aligned with respect to thecentral geometric axis “Y” of the profiling member 17 and thus, withrespect to the geometric axis of rotation “X” of the green tyre 2.

The relative movement between frame 49 and tailstock 48 determines thecorrect relative positioning along the geometric axis of rotation “X”corresponding to the axial gripping position.

As exemplified in FIG. 9, in the axial gripping position, the grippingareas 33 are placed at the axial centreline plane “M” of tyre 2 arrangedin the profiling unit 11.

Preferably, the lowering towards the axial gripping position is carriedout by maintaining the gripping elements 35 in the rest condition, thusreducing the risk of sliding and/or interference against the green tyre2. Upon reaching the axial gripping position, the above driving actuator37 can be activated, which causes the translation of the grippingelements 35 towards the working configuration, approaching the treadband 6 of tyre 2.

Moreover, it is further preferably provided that the lowering of thegripping device 30 towards the axial gripping position is carried outafter the beginning of the profiling operation of tyre 2, but beforesuch a profiling operation has been completed.

More in particular, such a lowering takes place for example when theprofiling member 17 has been returned to the contracted condition aftercarrying out at least one expansion action.

Upon reaching the working configuration, the gripping elements 35 may bestill slightly distanced with respect to tyre 2. In this case, a lastexpansion action imposed to the profiling member 17 brings the treadband 6 against the gripping elements 32, thus expanding the green tyrefrom the interior up to reaching the expanded configuration.

Alternatively, it may be provided that the radial contraction of thegripping elements 35 takes place when the profiling member 17 and thusthe green tyre has already reached the expanded condition following thelast expansion action. In this case, upon reaching the workingconfiguration, the gripping elements 35 come into contact with tyre 2,against the outer surface of the tread band 6 while the profiling member17 and thus the green tyre is preferably in the expanded condition.

In both cases, by means of the profiling unit 11, it is provided toexert a thrust action on a radially inner surface of the green tyredirected radially outwards for expanding the green tyre from theinterior up to reaching the expanded configuration (FIG. 10).

When the radially outer surface 2 b of the tire and the at least onegripping area 33 are in mutual contact, the pneumatic suction action isactivated.

The pneumatic suction effect produced by interface 45 makes the grippingelements 35 be operatively activated against a radially outer surface ofthe tread band 6, exerting attraction actions “A” directed in radialdistancing of the geometric axis of rotation “X” of tyre 2, anddistributed along the whole circumferential development of the latter(FIG. 10).

The engagement of tyre 2 to the transfer member 31 can thus be obtainedwhile tyre 2 itself is still mechanically retained by the profilingmember 17, which imposes retaining the cross-sectional convex profile ina radially outer direction.

Once the engagement has taken place, the profiling member 17 can bereturned to the radially contracted condition, so that tyre 2 can beaxially removed from the profiling unit 11 by the effect of the liftingof the gripping device 30. In other words, the thrust action whichbrings the green tyre to the expanded configuration is cancelled beforehandling the gripping device 30 (FIG. 11).

The attraction actions exerted on the tread band 6 by the grippingelements 35 mechanically retain tyre 2, thus ensuring the maintenance ofthe latter in the profiled condition even after the disengagementthereof from the profiling member 17. Tyre 2 is therefore adapted toretain a stable geometrical shape for the correct loading in thevulcanisation mould 101. In particular, retaining the profilingcondition favours the correct engagement of tyre 2 with the membersdesigned to the treatment thereof in the vulcanisation press.

In the case in which, as shown, the gripping sector 32 is arrangedcircumferentially around the gripping axis “Z” and defines an annulargripping portion, in order to pick up the green tyre from the profilingunit 11 it may be advantageously provided to select an annular grippingband “B” of the green tyre arranged around the geometric axis ofrotation “X” at a predetermined height along the geometric axis ofrotation itself.

In this case, in order to adjust the gripping device 30, it may beprovided to adjust the annular gripping portion to the adjustmentdiameter and subsequently bring the annular gripping portion in aradially outer position with respect to the annular gripping band “B”.The annular gripping portion is arranged at the height of the annulargripping band “B”, i.e. in the axial gripping position, for example bymeans of a relative axial translation movement between the annulargripping portion and the annular gripping band “B” to arrange them atthe same height along the geometric axis of rotation “X” of the greentyre (FIG. 9).

The annular gripping band “B” and the relative height are selected as afunction of the tyre width. Preferably, the annular gripping band “B” isan annular axial centreline band of the tyre and belongs to the treadband of the tyre.

Once the height of the annular gripping band “B” has been reached, it isprovided to adjust the annular gripping portion to the grippingdiameter. The gripping diameter coincides with the outer diameter of theannular gripping band “B” optionally in the expanded configuration, soas to activate the annular gripping portion against the annular grippingband “B”.

As described above with reference to the gripping elements 35, theadjustment of the annular gripping portion may be carried out byadjusting simultaneously and synchronously the radial position of allgripping areas or autonomously adjusting the radial position of eachgripping area.

The gripping area is thus activated against the radially outer surface 2b of the annular gripping band “B”. In particular, the annular grippingportion is placed in contact with the annular gripping band “B” toactivate the gripping area against the radially outer surface 2 b of thegreen tyre 2, and in particular to activate the pneumatic suctionaction.

The pneumatic suction effect produced through the annular grippingportion exerts the above attraction actions “A” directed radially awayof the geometric axis of rotation “X” of tyre 2, and distributed alongthe whole circumferential development of the latter.

As already described above, before moving the green tyre away from theprofiling unit 11, it is provided to cancel the thrust action that hasbrought it to the expanded configuration.

Once the tyre has been separated from the profiling unit 11, during thehandling of the gripping device, the green tyre 2 is retained by thegripping device 30 hanging only at the annular gripping band “B”.

Thereafter, with reference for example to FIGS. 16-18, the grippingdevice 30 which carries a second green tyre 2 is centred with respect tothe vulcanisation mould 101, by aligning the gripping axis “Z” andconsequently the geometric axis of rotation “X” with a reference axis“K” of the vulcanisation mould 101 (FIG. 16).

Preferably, it is provided to carry out a relative axial translationmovement between the gripping device 30 and the vulcanisation mould 101for bringing the axial centreline plane “M” of the green tyre 2 at anaxial reference 51 arranged at a predetermined height along thereference axis “K” of the vulcanisation mould 101 (FIG. 17).

Thereafter, it is provided to release the green tyre 2 in thevulcanisation mould 101, preferably in a suitable processing positionwith respect thereto (FIG. 18).

According to a possible embodiment, the vulcanisation mould 101comprises two half-moulds, of which FIGS. 16-18 show a lower half-mould102, and a central body 103 preferably movable with respect to the lowerhalf-mould 102. The upper half-mould is not shown. The reference axis“K” of the vulcanisation mould 101 corresponds to the reference axis ofthe central body 103 along which the central body itself is movable intranslation.

The central body 103 is configured for exerting a thrust action directedradially towards the exterior on a radially inner surface 2 a of thegreen tyre 2 so as to keep the green tyre 2 in position on the centralbody 103 by means of said thrust action.

The transfer member 31 and the central body 103 are configured forarranging the green tyre 2 held by the gripping device 30 in a radiallyouter position with respect to the central body 103.

Moreover, the transfer member 31 and the central body 103 are configuredfor axially positioning with respect to the central body 103 the greentyre 2 held by the gripping device 30 so that an axial centreline plane“M” of the green tyre is arranged at a predetermined height along thereference axis “K” of the central body 103, at the axial reference 51.

The centring group 47 a is configured for centring the green tyre 2 heldby the gripping device 30 with the central body 103 by aligning thegeometric axis of rotation “X” of the green tyre held by the grippingdevice 30 and consequently the reference axis “K” of the central body103.

The centring group 47 a is substantially similar to the centring group47 described above. The two groups in fact share the first centringportion associated with the gripping device 30, for example implementedby a tailstock 48.

In particular, the centring unit 47 a comprises the first centringportion associated with the gripping device 30 and a second centringportion associated with the central body 103. In particular, the firstand second centring portion define a shape coupling configured foraligning the gripping axis “Z” and the geometric axis of rotation “X” ofthe green tyre 2 held by the gripping device 30 with the reference axis“K” of the central body 103.

According to the embodiment shown, the second centring portionassociated to the central body 103 is implemented by a coupling shank 16a is similar to the above coupling shank 16 of the profiling unit 11.

The movement of the gripping device 30 from the profiling unit 11provides to load the green tyre 2 into the vulcanisation mould 101 forexample by releasing the green tyre 2 on the central body 103.

According to a possible embodiment of which the accompanying drawingsare a non-limiting example, the gripping device 30 and the central body103 are movable according to a relative axial translation movement forarranging the axial centreline plane “M” at the predetermined heightalong the reference axis “K” of the central body 103, i.e. at the axialreference 51.

Preferably, the central body 103 is movable between a vulcanisationposition, in which the central body itself is arranged within thevulcanisation mould 101 and in particular in the lower half-mould 102(FIG. 18), and a gripping position, in which the central body 103 isarranged outside the vulcanisation mould and in particular outside thelower half-mould 102, and positioned radially inside the green tyre 2(FIG. 17).

Preferably, the vulcanisation position is arranged at a smaller heightthan the gripping position, for example as shown in FIGS. 16-18.

The central body 103 comprises a support structure 104 arranged around acentral shaft 105 to which a central disc element 106 is centrallyfixed, preferably circular in shape, having a peripheral border whichextends concentrically to the reference axis “K”.

The coupling shank 16 a tubular in shape, having a truncated-cone upperend, is preferably fixed on an upper surface of the disc support element106, concentrically to the reference axis “K”.

The disc support element 106 is operatively coupled to a radiallyexpandable portion 107, extending circumferentially around the referenceaxis “K” and preferably arranged along the perimeter with respect to thedisc support element 106.

In other words, the central body 103 comprises at least one portion 107configured for expanding up to touching a radially inner surface of thegreen tyre.

Preferably, portion 107 is an expandable vulcanisation chamber, forexample implemented by an expandable bladder extending around thereference axis “K”. Preferably, the axial reference 51 is arranged at anaxial centreline plane of the expandable vulcanisation chamber.

The expandable bladder is preferably fixed around the disc supportelement 106 which has at least one channel 108 for the controlledintroduction of air or other operating fluid under pressure so that theabove bladder can expand radially away with respect to the referenceaxis “K”.

In a possible alternative embodiment not shown, the disc support element106 may optionally comprise, in addition to or in replacement of theexpandable collar, a plurality of sectors radially movable with respectto the reference axis “K”.

With reference to FIG. 16, the central body 103 with retracted portion107 is handled, in particular raised, from the vulcanisation position tothe gripping position.

With reference to FIG. 17, during the handling of the central body 103,the gripping axis “Z” of the gripping device 30 and the geometric axisof rotation “X” of the green tyre associated thereto are aligned withthe reference axis “K” of the central body 103. Such an alignment iscarried out by the mutual engagement between the coupling shank 16 a andtailstock 48.

The relative movement between frame 49 and tailstock 48 determines thecorrect relative positioning along the geometric axis of rotation “X”corresponding to the gripping position.

When the central body 103 reaches the gripping position and the axialcentreline plane M arranged at the predetermined height, the centralbody exerts the above thrust action on the radially inner surface 2 a ofthe green tyre 2 by the effect of the introduction of air or otheroperating fluid under pressure into portion 107. Portion 107 reaches themaximum radial expansion against the radially inner surface 2 a of thegreen tyre 2.

Preferably, the width of portion 107, i.e. the axial dimension thereof,in radial expansion configuration is smaller than the width of the greentyre 2 which, following the radial expansion of portion 107 and thenfollowing the interaction with the two half-moulds of the vulcanisationmould, embraces portion 107, thus taking the radial section that will bemade definitive by the vulcanisation.

Thereafter, the gripping device 30 is disengaged from the green tyre 2by deactivating the gripping area(s) and releasing the radially outersurface. The green tyre 2 is kept in position hanging on the centralbody 103 arranged in gripping position, retained from the interior bymeans of the thrust action exerted by the central body 103. Withreference to FIG. 18, keeping the green tyre 2 in position on thecentral body 103 by the above thrust action, the central body 103 ishandled, in particular lowered, from the gripping position to thevulcanisation position for vulcanising the green tyre 2. It should benoted that preferably, the green tyre 2 is retained from the interioronly by means of the thrust action exerted by the central body 103without bottom support.

After releasing the green tyre 2 to the vulcanisation mould 101, thetransfer member 31 repositions the gripping device 30 at the profilingunit 11 on which another tyre to be handled is made available.

According to a possible embodiment of which the accompanying figures area non-limiting example, apparatus 1 is configured for maintaining thecentral geometric axis “X” of the green tyre 2 arranged transverselywith respect to a horizontal geometric plane, preferably vertically.

In use, apparatus 1 as described above allows implementing a method forloading a green tyre for bicycle in a vulcanisation mould according tothe present invention, in which the gripping device 30 picks the greentyre 2 keeping it hanging, preferably only at the annular gripping band“B”. Preferably, the axial centreline plane “M” of the green tyre 2symmetrically divides the annular gripping band “B” with respectthereto.

The gripping device 30 that holds the green tyre 2 is handled up toaligning the gripping axis “Z” and thus the geometric axis of rotation“X” of the green tyre 2 with the reference axis “K” of the central body103.

The green tyre 2 is then arranged in a radially outer position withrespect to the central body 103 and axially positioned so that the axialcentreline plane “M” of the green tyre 2 is arranged at the axialreference 51. The green tyre 2 is axially arranged with respect to thecentral body 103 by carrying out a relative axial translation movementbetween the gripping device 30 and the central body 103.

The green tyre 2 is arranged and positioned with respect to the centralbody 103 arranged with the reference axis “K” arranged transversely withrespect to a horizontal geometric plane, preferably vertically.

The central body 103 exerts the above thrust action directed radiallytowards the exterior on the radially inner surface 2 a of the green tyre2 so as to keep the green tyre 2 on the central body 103 by means of,and preferably only, such a thrust action.

Finally, the gripping device 30 is disengaged from the green tyre 2 forreleasing the green tyre itself on the central body 103 with the axialcentreline plane “M” centred and positioned in an axial positioncorresponding to the predetermined height.

The invention claimed is:
 1. A method for loading a green tyre for abicycle in a vulcanisation mould, comprising: picking up the green tyreand hanging the green tyre by a gripping device defining a gripping axis(Z); aligning the gripping device, which holds the green tyre, up to ageometric axis of rotation (X) of the green tyre with a reference axis(K) of a central body of the vulcanisation mould; arranging the greentyre in a radially outer position with respect to the central body ofthe vulcanisation mould; axially positioning the green tyre with respectto the central body, wherein an axial centreline plane (M) of the greentyre is arranged at an axial reference arranged at a predeterminedheight along the reference axis (K) of the central body; exerting athrust action by the central body, wherein the thrust action is directedradially outwards on a radially inner surface of the green tyre; keepingthe green tyre in position on the central body by the thrust action; anddisengaging the gripping device from the green tyre to release the greentyre on the central body with the axial centreline plane (M) centred andpositioned in an axial position corresponding to the predeterminedheight, wherein picking up the green tyre comprises activating at leastone gripping area of a gripping sector of the gripping device against aradially outer surface of the green tyre, and the gripping deviceretains the green tyre from the exterior; and wherein activating thegripping area against the radially outer surface of the green tyrecomprises exerting an attraction force (A) on the radially outer surfaceof the green tyre moving away from the geometric axis of rotation (X).2. The method according to claim 1, wherein activating the gripping areaagainst the radially outer surface of the green tyre comprisescontacting the gripping area with the radially outer surface of thegreen tyre.
 3. The method according to claim 2, wherein the attractionforce (A) is exerted by a pneumatic suction action generating apredetermined degree of vacuum between the radially outer surface of thegreen tyre and the at least one gripping area.
 4. The method accordingto claim 3, wherein disengaging the gripping device from the green tyrecomprises deactivating the at least one gripping area to release theradially outer surface.
 5. The method according to claim 4, whereindisengaging the gripping device from the green tyre further comprisesdeactivating the pneumatic suction action to release the radially outersurface.
 6. The method according to claim 5, further comprising exertinga thrust action by a profiling unit, wherein the thrust action of theprofiling unit is directed radially outwards on a radially inner surfaceof the green tyre for expanding the green tyre from the interior up toreaching an expanded configuration prior to picking up the green tyre.7. The method according to claim 6, wherein picking up the green tyrecomprises activating at least one gripping area of a gripping sector ofthe gripping device against a radially outer surface of the green tyrein the expanded configuration to retain the green tyre from the exteriorand keep the green tyre in the expanded configuration.
 8. The methodaccording to claim 7, wherein the gripping sector is arrangedcircumferentially around the gripping axis (Z) and defines an annulargripping portion.
 9. The method according to claim 8, further comprisingselecting an annular gripping band (B) of the green tyre arranged aroundthe geometric axis of rotation (X) at a predetermined height along thegeometric axis of rotation (X) itself and activating the at least onegripping area of the annular gripping portion against the radially outersurface of the annular gripping band (B).
 10. The method according toclaim 9, wherein during the activation of the gripping device, the greentyre is retained by the gripping device and hangs only at the annulargripping band (B).
 11. The method according to claim 10, wherein theaxial centreline plane (M) of the green tyre symmetrically divides theannular gripping band (B) with respect thereto.
 12. The method accordingto claim 11, wherein axially positioning the green tyre with respect tothe central body comprises carrying out a relative axial translationmovement between the gripping device and the central body to arrange theaxial centreline plane (M) at the predetermined height along thereference axis (K) of the central body.
 13. The method according toclaim 12, wherein axially positioning the green tyre with respect to thecentral body further comprises handling the central body between avulcanisation position, wherein the central body is arranged within thevulcanisation mould, and a gripping position, wherein the central bodyis arranged outside the vulcanisation mould and positioned radiallyinside the green tyre.
 14. The method according to claim 13, wherein thecentral body exerts the thrust action on the radially inner surface ofthe green tyre when the central body reaches the gripping position andthe axial centreline plane (M) is arranged at the predetermined height.15. The method according to claim 14, wherein disengaging the grippingdevice from the green tyre, hanging the green tyre in position on thecentral body arranged in the gripping position, and retaining from theinterior by the thrust action exerted by the central body.
 16. Themethod according to claim 15, wherein handling the central body from thevulcanisation position to the gripping position, wherein the centralbody exerts the thrust action on the radially inner surface of the greentyre and, while keeping the green tyre in position on the central bodyby the thrust action, handling the central body from the grippingposition to the vulcanisation position for vulcanising the green tyre.17. The method according to claim 16, wherein exerting the thrust actionby the central body comprises radially expanding at least one portion ofthe central body to contact a radially inner surface of the green tyre.18. The method according to claim 17, wherein the green tyre is keptwith the geometric axis of rotation (X) arranged transversely withrespect to a horizontal geometric plane.
 19. The method according toclaim 18, wherein picking up the green tyre by the gripping device iswith the gripping axis (Z) and the geometric axis of rotation (X)arranged transversely with respect to a horizontal geometric plane. 20.The method according to claim 19, wherein axially positioning the greentyre with respect to the central body is transversely arranged withrespect to a horizontal geometric plane.